1981 GS550 Wont rev above 6-7k

[Guest]

Working on a '81 GS550L, Bike wont rev very high, and when its under load its even worse. I've cleaned carbs many of times and I can't figure out what it is any help would be much appreciated

[Spyder]

Does this bike, have stock airbox, and exhaust? And I have to ask, by "cleaned", exactly how are you cleaning them? How long have you had the bike? Is this a "all of a sudden" thing, or? More details on the history of the bike are needed. You have absolutely come to the right place for help with this bike.

OH! And welcome to the GSR !

[fastbysuzuki]

For info there is a carb tutorial here http://zeus.mtsac.edu/~cliff/storage...d_Tutorial.pdf

And yes welcome

[octusis]

Does this bike, have stock airbox, and exhaust? And I have to ask, by "cleaned", exactly how are you cleaning them? How long have you had the bike? Is this a "all of a sudden" thing, or? More details on the history of the bike are needed. You have absolutely come to the right place for help with this bike.

OH! And welcome to the GSR !

I've got pods and straight pipes on it, I've already jetted the mains up a size or 2 (can't remember exact) I took them apart atleast 2 or 3 times (fully) and cleaned them with compressed air and carb cleaner. I've had the bike for maybe a few months (bought off a buddy) and with everything stock it had the same issues. Thank you for the welcome and fast response

[octusis]

For info there is a carb tutorial here http://zeus.mtsac.edu/~cliff/storage...d_Tutorial.pdf

And yes welcome

That looks like it will come in really handy. I guess I should look into buying a rebuild kit for it, any you would suggest? Appreciate the fast response.

[Redman]

Welcome to TheGSR from west Michigan,

. . . . . . . . . . . . . . . . . . . at looks like it will come in really handy. I guess I should look into buying a rebuild kit for it, any you would suggest? . . . . . . . . . . . . . . . . . .

If by "rebuild kit" you mean new float needle and seat and other jets, the answer is "None".
Well, unless they are damaged.

If you mean O-rings, then the answer is Cycle ORings.

[Spyder]

Nobody here will suggest a rebuild kit here, lol. Straight pipes and pods will require more than 2 steps up in jet size. I would get stage 3 dyno jet kit, and an O-Ring set from Cycleorings.com He is a member here, and puts the o-ring kits together specifically for our bikes. Doesn't cost much either. the symptoms you have suggest a lean condition. VERY lean. If you follow the above cleaning and rebuild tutorial, you should be up and running long before we thaw out. Don't hesitate to ask questions. Only way to learn in my opinion...

[Rob S.]

...I would get stage 3 dyno jet kit, and an O-Ring set from Cycleorings.com.

Absolutely agree.

And worst comes to worst, you can learn to live with it. My Sporster refuses to rev much past 6k, and I was told there's nothing can be done about it.

[octusis]

Nobody here will suggest a rebuild kit here, lol. Straight pipes and pods will require more than 2 steps up in jet size. I would get stage 3 dyno jet kit, and an O-Ring set from Cycleorings.com He is a member here, and puts the o-ring kits together specifically for our bikes. Doesn't cost much either. the symptoms you have suggest a lean condition. VERY lean. If you follow the above cleaning and rebuild tutorial, you should be up and running long before we thaw out. Don't hesitate to ask questions. Only way to learn in my opinion...

These are the plugs if this helps, do these look too lean?
image.jpg

[fastbysuzuki]

These are the plugs if this helps, do these look too lean?
[ATTACH=CONFIG]59702[/ATTACH]

they look lean to me

[octusis]

they look lean to me

Should I try raising the needle? Buying bigger mains? Or something else that I don't know about? Thanks for response.

[Spyder]

Yes, those do look lean.

[timebombprod]

hey private message "chuck hahn" he knows about straightpipes and such but just know with straightpipes youll have to be tuning ur carbs a good amount of times no real set and forget tune for them. if ur not worried bout peak performance and like the loudness youll be fine but you do lose power from those straightpipes.

[LAB3]

One of the tricks to running straight pipes is to put "Lollypops" in the pipes to help generate some backpressure and reclaim that lost torque. Basically they're just a bolt with a washer welded onto them that's placed into the pipes. It's a cheap or even free solution out of a well stocked junk drawer. There's plenty of articles and YouTube videos out there on how to do it.

[octusis]

One of the tricks to running straight pipes is to put "Lollypops" in the pipes to help generate some backpressure and reclaim that lost torque. Basically they're just a bolt with a washer welded onto them that's placed into the pipes. It's a cheap or even free solution out of a well stocked junk drawer. There's plenty of articles and YouTube videos out there on how to do it.

I have looked into them, I may try it tomorrow in my free time and report back. Do they tend to need adjustment or should I just run the washers straight vertical to the pipe?